1. Field of the Invention
This invention relates in general to the cold rolling of metal strip. More specifically, it relates to a system for controlling the tension and camber (flatness) of the strip product.
2. The Prior Art
Camber defines the amount of edge curvature of a strip width of rolled sheet metal with reference to a straight edge. The prior art discloses a number of devices for effecting control of the strip camber. Typically, these prior art systems change the shape of one of the metal working rolls, by changing the temperature profile of the roll, responsive to signals received from a sensing element which monitors the strip product. U.S. Pat. No. 4,262,511 issued to Boisvert et al, for example, discloses a "shapemeter" in the form of a segmented rotor supported by an air cushion and in contact with the sheet metal product. Pneumatic signals from the segmented rotor are converted into electrical signals which, in turn, control the distribution of coolant onto the metal roll surfaces. The teachings of U.S. Pat. No. 3,499,306 issued to Pearson are somewhat similar.
The "shapemeters" of the two aforementioned patents, as noted above, are designed to operate in cooperation with apparatus for changing the profile of the working roll by changing distribution of coolant and the temperature profile of the roll. While such devices may successfully monitor shape across wide sheets, they are ineffective with narrow strip because the thermal gradient across the face of the roll over a distance corresponding to the width of the narrow strip is insignificant.
Conventional "tensiometers" simply monitor tension in the strip intermediate adjacent roll stands operating in tandem and have no capability for monitoring chamber. See, for example U.S. Pat. Nos. 2,345,765 and 2,544,467 issued to Michel.
Accordingly, it is an object of the present invention to provide a simple, relatively maintenance-free device for detection and continuous monitoring of the camber of a moving metal strip.
It is another object of the present invention to provide a tensiometer which has both tension measuring and camber measuring capabilities.
Yet another object is to provide a device for monitoring camber of a narrow strip.
Other objects and further scope of applicability of the present invention will become apparent from a reading of the detailed description to follow, taken in conjunction with the accompanying drawings.